/*
 * Copyright (c) 2012, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 */
/*
 * Copyright 1999-2004 The Apache Software Foundation.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
/*
 * $Id: XNodeSet.java,v 1.2.4.2 2005/09/14 20:34:45 jeffsuttor Exp $
 */
package com.sun.org.apache.xpath.internal.objects;

import com.sun.org.apache.xml.internal.dtm.DTM;
import com.sun.org.apache.xml.internal.dtm.DTMIterator;
import com.sun.org.apache.xml.internal.dtm.DTMManager;
import com.sun.org.apache.xml.internal.utils.XMLString;
import com.sun.org.apache.xpath.internal.NodeSetDTM;
import com.sun.org.apache.xpath.internal.axes.NodeSequence;

import org.w3c.dom.NodeList;
import org.w3c.dom.traversal.NodeIterator;

/**
 * This class represents an XPath nodeset object, and is capable of
 * converting the nodeset to other types, such as a string.
 * @xsl.usage general
 */
public class XNodeSet extends NodeSequence {
    static final long serialVersionUID = 1916026368035639667L;

    /**
     * Default constructor for derived objects.
     */
    protected XNodeSet() {
    }

    /**
     * Construct a XNodeSet object.
     *
     * @param val Value of the XNodeSet object
     */
    public XNodeSet(DTMIterator val) {
        super();
        if (val instanceof XNodeSet) {
            final XNodeSet nodeSet = (XNodeSet) val;
            setIter(nodeSet.m_iter);
            m_dtmMgr = nodeSet.m_dtmMgr;
            m_last = nodeSet.m_last;
            // First make sure the DTMIterator val has a cache,
            // so if it doesn't have one, make one.
            if (!nodeSet.hasCache())
                nodeSet.setShouldCacheNodes(true);

            // Get the cache from val and use it ourselves (we share it).
            setObject(nodeSet.getIteratorCache());
        } else
            setIter(val);
    }

    /**
     * Construct a XNodeSet object.
     *
     * @param val Value of the XNodeSet object
     */
    public XNodeSet(XNodeSet val) {
        super();
        setIter(val.m_iter);
        m_dtmMgr = val.m_dtmMgr;
        m_last = val.m_last;
        if (!val.hasCache())
            val.setShouldCacheNodes(true);
        setObject(val.m_obj);
    }

    /**
     * Construct an empty XNodeSet object.  This is used to create a mutable
     * nodeset to which random nodes may be added.
     */
    public XNodeSet(DTMManager dtmMgr) {
        this(DTM.NULL, dtmMgr);
    }

    /**
     * Construct a XNodeSet object for one node.
     *
     * @param n Node to add to the new XNodeSet object
     */
    public XNodeSet(int n, DTMManager dtmMgr) {

        super(new NodeSetDTM(dtmMgr));
        m_dtmMgr = dtmMgr;

        if (DTM.NULL != n) {
            ((NodeSetDTM) m_obj).addNode(n);
            m_last = 1;
        } else
            m_last = 0;
    }

    /**
     * Tell that this is a CLASS_NODESET.
     *
     * @return type CLASS_NODESET
     */
    public int getType() {
        return CLASS_NODESET;
    }

    /**
     * Given a request type, return the equivalent string.
     * For diagnostic purposes.
     *
     * @return type string "#NODESET"
     */
    public String getTypeString() {
        return "#NODESET";
    }

    /**
     * Get numeric value of the string conversion from a single node.
     *
     * @param n Node to convert
     *
     * @return numeric value of the string conversion from a single node.
     */
    public double getNumberFromNode(int n) {
        XMLString xstr = m_dtmMgr.getDTM(n).getStringValue(n);
        return xstr.toDouble();
    }

    /**
     * Cast result object to a number.
     *
     * @return numeric value of the string conversion from the
     * next node in the NodeSetDTM, or NAN if no node was found
     */
    public double num() {

        int node = item(0);
        return (node != DTM.NULL) ? getNumberFromNode(node) : Double.NaN;
    }

    /**
     * Cast result object to a number, but allow side effects, such as the
     * incrementing of an iterator.
     *
     * @return numeric value of the string conversion from the
     * next node in the NodeSetDTM, or NAN if no node was found
     */
    public double numWithSideEffects() {
        int node = nextNode();

        return (node != DTM.NULL) ? getNumberFromNode(node) : Double.NaN;
    }

    /**
     * Cast result object to a boolean.
     *
     * @return True if there is a next node in the nodeset
     */
    public boolean bool() {
        return (item(0) != DTM.NULL);
    }

    /**
     * Cast result object to a boolean, but allow side effects, such as the
     * incrementing of an iterator.
     *
     * @return True if there is a next node in the nodeset
     */
    public boolean boolWithSideEffects() {
        return (nextNode() != DTM.NULL);
    }

    /**
     * Get the string conversion from a single node.
     *
     * @param n Node to convert
     *
     * @return the string conversion from a single node.
     */
    public XMLString getStringFromNode(int n) {
        // %OPT%
        // I guess we'll have to get a static instance of the DTM manager...
        if (DTM.NULL != n) {
            return m_dtmMgr.getDTM(n).getStringValue(n);
        } else {
            return com.sun.org.apache.xpath.internal.objects.XString.EMPTYSTRING;
        }
    }

    /**
     * Directly call the
     * characters method on the passed ContentHandler for the
     * string-value. Multiple calls to the
     * ContentHandler's characters methods may well occur for a single call to
     * this method.
     *
     * @param ch A non-null reference to a ContentHandler.
     *
     * @throws org.xml.sax.SAXException
     */
    public void dispatchCharactersEvents(org.xml.sax.ContentHandler ch) throws org.xml.sax.SAXException {
        int node = item(0);

        if (node != DTM.NULL) {
            m_dtmMgr.getDTM(node).dispatchCharactersEvents(node, ch, false);
        }

    }

    /**
     * Cast result object to an XMLString.
     *
     * @return The document fragment node data or the empty string.
     */
    public XMLString xstr() {
        int node = item(0);
        return (node != DTM.NULL) ? getStringFromNode(node) : XString.EMPTYSTRING;
    }

    /**
     * Cast result object to a string.
     *
     * @return The string this wraps or the empty string if null
     */
    public void appendToFsb(com.sun.org.apache.xml.internal.utils.FastStringBuffer fsb) {
        XString xstring = (XString) xstr();
        xstring.appendToFsb(fsb);
    }

    /**
     * Cast result object to a string.
     *
     * @return the string conversion from the next node in the nodeset
     * or "" if there is no next node
     */
    public String str() {
        int node = item(0);
        return (node != DTM.NULL) ? getStringFromNode(node).toString() : "";
    }

    /**
     * Return a java object that's closest to the representation
     * that should be handed to an extension.
     *
     * @return The object that this class wraps
     */
    public Object object() {
        if (null == m_obj)
            return this;
        else
            return m_obj;
    }

    // %REVIEW%
    // hmmm...
    //  /**
    //   * Cast result object to a result tree fragment.
    //   *
    //   * @param support The XPath context to use for the conversion
    //   *
    //   * @return the nodeset as a result tree fragment.
    //   */
    //  public DocumentFragment rtree(XPathContext support)
    //  {
    //    DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
    //    DocumentBuilder db = dbf.newDocumentBuilder();
    //    Document myDoc = db.newDocument();
    //
    //    DocumentFragment docFrag = myDoc.createDocumentFragment();
    //
    //    DTMIterator nl = iter();
    //    int node;
    //
    //    while (DTM.NULL != (node = nl.nextNode()))
    //    {
    //      frag.appendChild(node, true, true);
    //    }
    //
    //    return frag.getDocument();
    //  }

    /**
     * Cast result object to a nodelist.
     *
     * @return a NodeIterator.
     *
     * @throws javax.xml.transform.TransformerException
     */
    public NodeIterator nodeset() throws javax.xml.transform.TransformerException {
        return new com.sun.org.apache.xml.internal.dtm.ref.DTMNodeIterator(iter());
    }

    /**
     * Cast result object to a nodelist.
     *
     * @return a NodeList.
     *
     * @throws javax.xml.transform.TransformerException
     */
    public NodeList nodelist() throws javax.xml.transform.TransformerException {
        com.sun.org.apache.xml.internal.dtm.ref.DTMNodeList nodelist = new com.sun.org.apache.xml.internal.dtm.ref.DTMNodeList(this);
        // Creating a DTMNodeList has the side-effect that it will create a clone
        // XNodeSet with cache and run m_iter to the end. You cannot get any node
        // from m_iter after this call. As a fix, we call SetVector() on the clone's
        // cache. See Bugzilla 14406.
        XNodeSet clone = (XNodeSet) nodelist.getDTMIterator();
        SetVector(clone.getVector());
        return nodelist;
    }

    //  /**
    //   * Return a java object that's closest to the representation
    //   * that should be handed to an extension.
    //   *
    //   * @return The object that this class wraps
    //   */
    //  public Object object()
    //  {
    //    return new com.sun.org.apache.xml.internal.dtm.ref.DTMNodeList(iter());
    //  }

    /**
     * Return the iterator without cloning, etc.
     */
    public DTMIterator iterRaw() {
        return this;
    }

    public void release(DTMIterator iter) {
    }

    /**
     * Cast result object to a nodelist.
     *
     * @return The nodeset as a nodelist
     */
    public DTMIterator iter() {
        try {
            if (hasCache())
                return cloneWithReset();
            else
                return this; // don't bother to clone... won't do any good!
        } catch (CloneNotSupportedException cnse) {
            throw new RuntimeException(cnse.getMessage());
        }
    }

    /**
     * Get a fresh copy of the object.  For use with variables.
     *
     * @return A fresh nodelist.
     */
    public XObject getFresh() {
        try {
            if (hasCache())
                return (XObject) cloneWithReset();
            else
                return this; // don't bother to clone... won't do any good!
        } catch (CloneNotSupportedException cnse) {
            throw new RuntimeException(cnse.getMessage());
        }
    }

    /**
     * Cast result object to a mutableNodeset.
     *
     * @return The nodeset as a mutableNodeset
     */
    public NodeSetDTM mutableNodeset() {
        NodeSetDTM mnl;

        if (m_obj instanceof NodeSetDTM) {
            mnl = (NodeSetDTM) m_obj;
        } else {
            mnl = new NodeSetDTM(iter());
            setObject(mnl);
            setCurrentPos(0);
        }

        return mnl;
    }

    /** Less than comparator         */
    static final LessThanComparator S_LT = new LessThanComparator();

    /** Less than or equal comparator          */
    static final LessThanOrEqualComparator S_LTE = new LessThanOrEqualComparator();

    /** Greater than comparator         */
    static final GreaterThanComparator S_GT = new GreaterThanComparator();

    /** Greater than or equal comparator          */
    static final GreaterThanOrEqualComparator S_GTE = new GreaterThanOrEqualComparator();

    /** Equal comparator         */
    static final EqualComparator S_EQ = new EqualComparator();

    /** Not equal comparator         */
    static final NotEqualComparator S_NEQ = new NotEqualComparator();

    /**
     * Tell if one object is less than the other.
     *
     * @param obj2 Object to compare this nodeset to
     * @param comparator Comparator to use
     *
     * @return See the comments below for each object type comparison
     *
     * @throws javax.xml.transform.TransformerException
     */
    public boolean compare(XObject obj2, Comparator comparator) throws javax.xml.transform.TransformerException {

        boolean result = false;
        int type = obj2.getType();

        if (XObject.CLASS_NODESET == type) {
            // %OPT% This should be XMLString based instead of string based...

            // From http://www.w3.org/TR/xpath:
            // If both objects to be compared are node-sets, then the comparison
            // will be true if and only if there is a node in the first node-set
            // and a node in the second node-set such that the result of performing
            // the comparison on the string-values of the two nodes is true.
            // Note this little gem from the draft:
            // NOTE: If $x is bound to a node-set, then $x="foo"
            // does not mean the same as not($x!="foo"): the former
            // is true if and only if some node in $x has the string-value
            // foo; the latter is true if and only if all nodes in $x have
            // the string-value foo.
            DTMIterator list1 = iterRaw();
            DTMIterator list2 = ((XNodeSet) obj2).iterRaw();
            int node1;
            java.util.Vector node2Strings = null;

            while (DTM.NULL != (node1 = list1.nextNode())) {
                XMLString s1 = getStringFromNode(node1);

                if (null == node2Strings) {
                    int node2;

                    while (DTM.NULL != (node2 = list2.nextNode())) {
                        XMLString s2 = getStringFromNode(node2);

                        if (comparator.compareStrings(s1, s2)) {
                            result = true;

                            break;
                        }

                        if (null == node2Strings)
                            node2Strings = new java.util.Vector();

                        node2Strings.addElement(s2);
                    }
                } else {
                    int n = node2Strings.size();

                    for (int i = 0; i < n; i++) {
                        if (comparator.compareStrings(s1, (XMLString) node2Strings.elementAt(i))) {
                            result = true;

                            break;
                        }
                    }
                }
            }
            list1.reset();
            list2.reset();
        } else if (XObject.CLASS_BOOLEAN == type) {

            // From http://www.w3.org/TR/xpath:
            // If one object to be compared is a node-set and the other is a boolean,
            // then the comparison will be true if and only if the result of
            // performing the comparison on the boolean and on the result of
            // converting the node-set to a boolean using the boolean function
            // is true.
            double num1 = bool() ? 1.0 : 0.0;
            double num2 = obj2.num();

            result = comparator.compareNumbers(num1, num2);
        } else if (XObject.CLASS_NUMBER == type) {

            // From http://www.w3.org/TR/xpath:
            // If one object to be compared is a node-set and the other is a number,
            // then the comparison will be true if and only if there is a
            // node in the node-set such that the result of performing the
            // comparison on the number to be compared and on the result of
            // converting the string-value of that node to a number using
            // the number function is true.
            DTMIterator list1 = iterRaw();
            double num2 = obj2.num();
            int node;

            while (DTM.NULL != (node = list1.nextNode())) {
                double num1 = getNumberFromNode(node);

                if (comparator.compareNumbers(num1, num2)) {
                    result = true;

                    break;
                }
            }
            list1.reset();
        } else if (XObject.CLASS_RTREEFRAG == type) {
            XMLString s2 = obj2.xstr();
            DTMIterator list1 = iterRaw();
            int node;

            while (DTM.NULL != (node = list1.nextNode())) {
                XMLString s1 = getStringFromNode(node);

                if (comparator.compareStrings(s1, s2)) {
                    result = true;

                    break;
                }
            }
            list1.reset();
        } else if (XObject.CLASS_STRING == type) {

            // From http://www.w3.org/TR/xpath:
            // If one object to be compared is a node-set and the other is a
            // string, then the comparison will be true if and only if there
            // is a node in the node-set such that the result of performing
            // the comparison on the string-value of the node and the other
            // string is true.
            XMLString s2 = obj2.xstr();
            DTMIterator list1 = iterRaw();
            int node;

            while (DTM.NULL != (node = list1.nextNode())) {
                XMLString s1 = getStringFromNode(node);
                if (comparator.compareStrings(s1, s2)) {
                    result = true;

                    break;
                }
            }
            list1.reset();
        } else {
            result = comparator.compareNumbers(this.num(), obj2.num());
        }

        return result;
    }

    /**
     * Tell if one object is less than the other.
     *
     * @param obj2 object to compare this nodeset to
     *
     * @return see this.compare(...)
     *
     * @throws javax.xml.transform.TransformerException
     */
    public boolean lessThan(XObject obj2) throws javax.xml.transform.TransformerException {
        return compare(obj2, S_LT);
    }

    /**
     * Tell if one object is less than or equal to the other.
     *
     * @param obj2 object to compare this nodeset to
     *
     * @return see this.compare(...)
     *
     * @throws javax.xml.transform.TransformerException
     */
    public boolean lessThanOrEqual(XObject obj2) throws javax.xml.transform.TransformerException {
        return compare(obj2, S_LTE);
    }

    /**
     * Tell if one object is less than the other.
     *
     * @param obj2 object to compare this nodeset to
     *
     * @return see this.compare(...)
     *
     * @throws javax.xml.transform.TransformerException
     */
    public boolean greaterThan(XObject obj2) throws javax.xml.transform.TransformerException {
        return compare(obj2, S_GT);
    }

    /**
     * Tell if one object is less than the other.
     *
     * @param obj2 object to compare this nodeset to
     *
     * @return see this.compare(...)
     *
     * @throws javax.xml.transform.TransformerException
     */
    public boolean greaterThanOrEqual(XObject obj2) throws javax.xml.transform.TransformerException {
        return compare(obj2, S_GTE);
    }

    /**
     * Tell if two objects are functionally equal.
     *
     * @param obj2 object to compare this nodeset to
     *
     * @return see this.compare(...)
     *
     * @throws javax.xml.transform.TransformerException
     */
    public boolean equals(XObject obj2) {
        try {
            return compare(obj2, S_EQ);
        } catch (javax.xml.transform.TransformerException te) {
            throw new com.sun.org.apache.xml.internal.utils.WrappedRuntimeException(te);
        }
    }

    /**
     * Tell if two objects are functionally not equal.
     *
     * @param obj2 object to compare this nodeset to
     *
     * @return see this.compare(...)
     *
     * @throws javax.xml.transform.TransformerException
     */
    public boolean notEquals(XObject obj2) throws javax.xml.transform.TransformerException {
        return compare(obj2, S_NEQ);
    }
}

/**
 * compares nodes for various boolean operations.
 */
abstract class Comparator {

    /**
     * Compare two strings
     *
     *
     * @param s1 First string to compare
     * @param s2 Second String to compare
     *
     * @return Whether the strings are equal or not
     */
    abstract boolean compareStrings(XMLString s1, XMLString s2);

    /**
     * Compare two numbers
     *
     *
     * @param n1 First number to compare
     * @param n2 Second number to compare
     *
     * @return Whether the numbers are equal or not
     */
    abstract boolean compareNumbers(double n1, double n2);
}

/**
 * Compare strings or numbers for less than.
 */
class LessThanComparator extends Comparator {

    /**
     * Compare two strings for less than.
     *
     *
     * @param s1 First string to compare
     * @param s2 Second String to compare
     *
     * @return True if s1 is less than s2
     */
    boolean compareStrings(XMLString s1, XMLString s2) {
        return (s1.toDouble() < s2.toDouble());
        // return s1.compareTo(s2) < 0;
    }

    /**
     * Compare two numbers for less than.
     *
     *
     * @param n1 First number to compare
     * @param n2 Second number to compare
     *
     * @return true if n1 is less than n2
     */
    boolean compareNumbers(double n1, double n2) {
        return n1 < n2;
    }
}

/**
 * Compare strings or numbers for less than or equal.
 */
class LessThanOrEqualComparator extends Comparator {

    /**
     * Compare two strings for less than or equal.
     *
     *
     * @param s1 First string to compare
     * @param s2 Second String to compare
     *
     * @return true if s1 is less than or equal to s2
     */
    boolean compareStrings(XMLString s1, XMLString s2) {
        return (s1.toDouble() <= s2.toDouble());
        // return s1.compareTo(s2) <= 0;
    }

    /**
     * Compare two numbers for less than or equal.
     *
     *
     * @param n1 First number to compare
     * @param n2 Second number to compare
     *
     * @return true if n1 is less than or equal to n2
     */
    boolean compareNumbers(double n1, double n2) {
        return n1 <= n2;
    }
}

/**
 * Compare strings or numbers for greater than.
 */
class GreaterThanComparator extends Comparator {

    /**
     * Compare two strings for greater than.
     *
     *
     * @param s1 First string to compare
     * @param s2 Second String to compare
     *
     * @return true if s1 is greater than s2
     */
    boolean compareStrings(XMLString s1, XMLString s2) {
        return (s1.toDouble() > s2.toDouble());
        // return s1.compareTo(s2) > 0;
    }

    /**
     * Compare two numbers for greater than.
     *
     *
     * @param n1 First number to compare
     * @param n2 Second number to compare
     *
     * @return true if n1 is greater than n2
     */
    boolean compareNumbers(double n1, double n2) {
        return n1 > n2;
    }
}

/**
 * Compare strings or numbers for greater than or equal.
 */
class GreaterThanOrEqualComparator extends Comparator {

    /**
     * Compare two strings for greater than or equal.
     *
     *
     * @param s1 First string to compare
     * @param s2 Second String to compare
     *
     * @return true if s1 is greater than or equal to s2
     */
    boolean compareStrings(XMLString s1, XMLString s2) {
        return (s1.toDouble() >= s2.toDouble());
        // return s1.compareTo(s2) >= 0;
    }

    /**
     * Compare two numbers for greater than or equal.
     *
     *
     * @param n1 First number to compare
     * @param n2 Second number to compare
     *
     * @return true if n1 is greater than or equal to n2
     */
    boolean compareNumbers(double n1, double n2) {
        return n1 >= n2;
    }
}

/**
 * Compare strings or numbers for equality.
 */
class EqualComparator extends Comparator {

    /**
     * Compare two strings for equality.
     *
     *
     * @param s1 First string to compare
     * @param s2 Second String to compare
     *
     * @return true if s1 is equal to s2
     */
    boolean compareStrings(XMLString s1, XMLString s2) {
        return s1.equals(s2);
    }

    /**
     * Compare two numbers for equality.
     *
     *
     * @param n1 First number to compare
     * @param n2 Second number to compare
     *
     * @return true if n1 is equal to n2
     */
    boolean compareNumbers(double n1, double n2) {
        return n1 == n2;
    }
}

/**
 * Compare strings or numbers for non-equality.
 */
class NotEqualComparator extends Comparator {

    /**
     * Compare two strings for non-equality.
     *
     *
     * @param s1 First string to compare
     * @param s2 Second String to compare
     *
     * @return true if s1 is not equal to s2
     */
    boolean compareStrings(XMLString s1, XMLString s2) {
        return !s1.equals(s2);
    }

    /**
     * Compare two numbers for non-equality.
     *
     *
     * @param n1 First number to compare
     * @param n2 Second number to compare
     *
     * @return true if n1 is not equal to n2
     */
    boolean compareNumbers(double n1, double n2) {
        return n1 != n2;
    }
}
